Fig. 1. Structure diagram of metamaterial absorber （a）Absorber structural unit, （b） cell structure side view, （c）equivalent circuit diagram of metamaterial resonator

Fig. 2. Reflection and absorption spectra of terahertz metamaterial absorbers without illumination

Fig. 3. The upper and lower surface current distribution of the absorber without illumination （a）0.821 THz, （b）3.929 THz

Fig. 4. Absorption spectra of metamaterials with different structural parameters （a） Absorption curves of different opening lengths, （b） absorption curves of different line widths, （c） absorption curves of different thickness of dielectric layers

Fig. 5. Characteristics of photosensitive silicon, （a） spectral characteristics，（b） illumination characteristics

Fig. 6. Terahertz metamaterial absorption spectra of silicon at different conductivities

Fig. 7. The upper and lower surface current distributions of the absorber with illumination （a）4.997 THz，σ =880 S/m；（b）1.846 THz，σ =1650 S/m；（c）3.091 THz，σ =1650 S/m；（d）5.676 THz，σ =5840 S/m；（e）1.197 THz，σ =1.055×10⁵ S/m；（f）5.499 THz，σ =2.7×10⁵ S/m；（g）3.546 THz，σ =3.65×10⁵ S/m；（h）4.584 THz，σ =1.9×10⁶ S/m